The Scale Aviators Forum Page

Advantages of petrol engines for model aircraft: - Petrol has a greater energy density than methanol so you only have to burn about 1/2 as much for the same power output, If it is a fours stroke petrol engine it is even noticeably more efficent again..The net effect of this is that you have to carry less fuel on board. - Petrol is cheaper than methanol/nitro/oil mix, so running costs are down. - The oil ratio is much much less that with methanol, petrol / oil ratios can be 40: 1 of higher, so much less mess on your air frame. I run 20:1 because a lot of my engines are foustrokes and they need higher oil content for some very good reasions. Two two stroke also dont mind 20:1 so thats what they get also. Never fouled a plug and very little oil mess after many flights, easly cleaned with Prepsol ( Prepsol is a wide boiling range, low aromatics, and hydrocarbon solvent Prepsol has high solvency for greases, oils and silicones making it ideal for cleaning surfaces prior to painting.) - Electronic ignition means more reliable running. - More elaborate carburetors that compensate for barometric pressure, less tuning required. - No rust problems with bearings like you get with methanol Disadvantages - More volatile fuel, higher fire risk. - Usually larger engines, but both OS and Saito make small petrol engines that are fantastic.

We have a few Gee bee's in our club, I have 11 last count, Peter is catching up fast ...... My Gee Bee Y I have been flying for years It has a MVVS 35cc petrol engine which is just fantastic. This thing Knife edges from horizon to Horizon. It started to develop a crack in the covering just behind the pilot. This crack started small (about 1mm  running from the top back edge of the cockpit). It just grew in the space of one trip to about 30mm long. Trip to Shepperton some 700KMs. The carry frame does not support the tail wheel and i think this crack formed in transport not flying. This was a good opportunity to recover the bird using my trusted and proven Acetate and dope. When I  ripped the covering off,  the crack was only cosmetic as the tails has a internal frame  that supports  the load. The crack just formed when some stringers became loose. So the following photos show the covering coming off and the Acetate being applied. This will then be dopes and painted. This gives a much better scale and better looking covering. It took about 5 hours to cover the fuze in acetate It is then dopes and painted. A picture tell a thousand words,, please comment if you want more information Please note the pin stripes are as they should be Dark blue.................

I needed a scale dummy engine for my 1/3 Sopwith Pup This was drawn using computor aided design software and then an STL file was geerated. The stl file was then loaded into the 3D printer software and printed on the 3D Printer. The parts as ABS plastic and are very strong. They parts can be printed with different filling options so the parts can be made light as well as strong. You will ususlly need nose weight in any WW! aircraft. I printed this light because it is alway better to add lightness. I balanced the front of the aircraft (Saito FG 57 Twin) with the engine and two speakers for the sound system 100 watts of sound.. The way I mounted the dummy engine and the sound system is works reall well, It easly slides out for access to the engine, as it is mounted on dowles The dummy motor was then painted and mounted in the cowl.------ Spark plugs before painting The wooden dowls slide into tubes in the fire wall, so they can easly be removed for serviceing the engine..